TW200836385A - Electric energy storage device - Google Patents

Abstract

To provide an energy storage device with high electric capacitance in relation to an electrical double layer storage device. The energy storage device comprises a positive electrode material containing graphite, a negative electrode material containing an oxide of at least one metal element selected from Ti, Zr, V, Cr, Mo, Mn, Fe, Co, Ni, Cu, Zn, Sn, Sb, Bi, W and Ta, which may preferably contains a metal oxide containing at least Ti as a metal element, and an electrolyte solution. This energy storage device has high capacitance and high discharge voltage, thereby having high energy, and the device can have high energy density, while being excellent in cycle characteristics and rate characteristics.

Description

200836385 IX. Description of the Invention [Technical Field of the Invention] The present invention relates to a power storage device having a large capacitance. [Prior Art] A power storage device having a positive electrode, a negative electrode, and a non-aqueous electrolyte as a main component has been proposed so far, and has been put into practical use in power storage and power storage systems for mobile devices, and standby power supplies for personal computers. . Among them, the electric storage device using graphite as the positive electrode material and the carbonaceous material as the negative electrode material is superior in electric capacity and withstand voltage compared with the conventional electric storage device using activated carbon as an electrode (refer to the patent literature). [Patent Document 1] Japanese Laid-Open Patent Publication No. 2005-294780 (Invention) The electric double-layer power storage device described in Patent Document 1 has capacitance and resistance as described above. Excellent voltage performance' However, power storage devices with larger capacitance are still expected. (Means for Solving the Problem) The inventors of the present invention have found that the electric storage device including the cathode material containing graphite, the anode material containing a specific metal oxide, and the electrolytic solution not only has a capacitance. Large, and An-5-200836385 is qualitative and safe, and the present invention can be completed. That is, the present invention is a cathode material containing graphite, which is selected from the group consisting of

Ti, Zr, V, Cr, Mo, Mn, Fe, Co, Ni, Cu, Zn, Sn,

A negative electrode material of an oxide of at least one of the metal elements of Sb, Bi, W, and Ta, and a storage device for the electrolytic solution. (Effect of the Invention) Since the power storage device of the present invention uses a negative electrode material containing a specific metal oxide, the capacitance increases. The cathode material containing graphite can be charged and discharged at a high voltage to achieve high energy density. In particular, in the present invention, high output is achieved by using graphite as a positive electrode and a specific metal oxide as a negative electrode. [Embodiment] The power storage device of the present invention is characterized by comprising a cathode material containing graphite and containing a material selected from the group consisting of Ti, Zr, V, Cr, Mo, Mn, Fe, Co, Ni, Cu, Zn, Sn, Sb, and Bi. a negative electrode material of an oxide of at least one metal element in W and Ta, and an electrolyte solution. In the present invention, as the negative electrode material, at least one metal selected from the group consisting of butyl sulfonium, 2, yttrium, lanthanum, Mn, Fe, Co, Ni, Cu, Zn, Sn, Sb, Bi, W, and Ta is used. The oxide of the element. When the metal oxide containing at least titanium is used as the oxide of the metal element, the capacitance can be increased, which is preferable. Further, in the case of using an electrolyte containing a lithium salt, if the oxidation-reduction potential of lithium is 0 V, the potential of the redox-6 - 200836385 containing the metal oxide of titanium is 1 to 2 V, due to lithium. It is said to be very high, and it can suppress the precipitation of metallic lithium to the negative electrode, so that the safety is also high, and more preferably titanium oxide and a composite oxide of titanium and an alkali metal or alkaline earth metal element. The composite oxide may, for example, be lithium titanate/calcium titanate, barium titanate or strontium carbonate, or a layered titanate alkali metal represented by M2Ti307 (M represents an alkali metal). The shape of the particles is not particularly limited as long as it is an isotropic shape such as a polyhedral shape, an anisotropic shape such as a rod shape, a fiber shape, or a sheet shape. Further, insofar as the effect of the present invention is not impaired, the surface of the oxide of the undoped other impurity metal or the surface of the oxide may be an inorganic substance such as cerium oxide or aluminum oxide, a surfactant, and a coupling agent. The organic matter is subjected to surface treatment. Among the above metal oxides, titanium oxide is particularly preferred because of its crystal lattice stability. Further, the titanium oxide in the present invention contains a compound of titanium and oxygen, a hydrogen-containing compound, an aqueous compound, or a hydrate, and examples thereof include titanium oxide (titanium dioxide, titanium oxynitride, titanium oxide, etc.), and titanium. Oxygen compound (dihydrogenitride (metadanic acid), tetrahydrogenitride (orthotitanic acid), with H2Ti3〇7 to χ4χ/3Τί(2·χ)/3〇4 (Χ = 〇.50 ～1.0) (such as a layered titanium oxide compound or the like), titanium hydroxide (such as titanium tetrahydrogen oxide), or the like. The particle size of the titanium oxide is not particularly limited, and a high output input consideration is required. Preferably, the specific surface area is in the range of 0.1 to 500 m 2 /g. In the present invention, as the titanium oxide, a crystallized or amorphous type such as a rutile type, a brookite type, an anatase type, a bronze type, or a ramsdellite type may be used. One is only anatase and/or rutile titanium oxide, the reason is that 200836385 has better capacitance than other titanium oxides. Particularly preferably, the anatase type has a specific surface area of 5 to 500 m 2 /g, and particularly preferably in the range of 5 to 350 m 2 /g. Further, more preferably, the rutile type has a specific surface area of 50 to 500 m 2 /g, and particularly preferably in the range of 50 to 3 500 m 2 /g. Alternatively, a titanium oxide obtained by heating a layered titanium oxide compound may be used. Specifically, the titanium oxide described in the specification of Japanese Patent Application No. 2007-22 1 3 1 1 and Japanese Patent Application No. 2007-223722 can be cited. That is, the titanium oxide described in Japanese Patent Application No. 2007-22 1 3 1 1 is a layer of titanium oxide compound represented by H2Ti307 at a temperature range of 200 to 350 ° C (above 260 °). C, the range of less than 3〇〇t: is good), and the heat-burning is carried out in the specification, and the compound oxide described in the specification of 2007-223 722 is H4x/3Ti(2-x)/ The layered titanium oxide compound represented by 3〇4 (x = 〇.50 to 1.0) is heated and fired in a temperature range of 250 to 45 °C. Titanium oxide can be used by assembling primary particles into secondary particles. The secondary particles in the present invention are in a state in which the primary particles are strongly bonded to each other, and are not aggregated or mechanically compacted by intergranular phase interaction such as van der Waals force, and are usually mixed, disintegrated, and filtered. Industrial washing under water washing, transportation, weighing, bagging, stacking, etc. does not easily disintegrate, and almost all exist in the state of secondary particles. The amount of voids of the secondary particles is preferably in the range of 0.005 to 1.0 cm 3 /g in terms of battery characteristics, and more preferably in the range of 〜·〇 5 to 1.0 cm 3 /g. The average particle diameter of the secondary particles (the particle diameter of 50% by the laser scattering method) is preferably in the range of 〇·5 to 1 μm in terms of electrode fabrication. -8- 200836385 In addition, if the average particle size of the primary particles (the 50% of the median diameter obtained by electron microscopy) is in the range of 1 to 500 nm, it is easy to obtain the desired amount of voids, 1 to 1 0 0 nm. The range is better. The specific surface area is not particularly limited, and is preferably in the range of 0.1 to 200 m 2 /g, and particularly preferably in the range of 3 to 200 m 2 /g. Further, the shape of the particles is not limited, and various shapes such as an isotropic shape and an anisotropic shape may be used. Further, in the present invention, a titanium oxide having a particle shape of a sheet may be used, and the flaky particles usually include a plate, a sheet, or a flake. The size of the flaky particles is preferably in the range of 1 to 1 〇〇 nm in thickness, and in the range of 0.1 to 500 //m in length and length. Alternatively, a fine flaky particle called a nanosheet may be used, and the thickness is in the range of 0.5 to 100 nm, and the width and length are in the range of 0·1 to 3 0 // m, respectively, to a thickness of 〇. The range of 5 to 10 nm, and the range of width and length of 1 to 10/zm are more preferable. Further, the graphite used for the positive electrode material in the present invention is not particularly limited. In the present invention, "graphite" means a range in which d (QQ2) obtained from the peak position of the X-ray diffraction 〇〇 2 surface is in the range of 0.33 5 to 0.344 nm. Among them, graphite having a specific surface area of 0.5 to 300 m2/g is preferred, and a range of .5 to 100 m2/g is more preferable. As the electrolytic solution for immersing the above positive electrode and negative electrode, for example, a solute can be dissolved in a nonaqueous solvent. The anion acting in the electrolytic solution may be selected from the group consisting of 4 fluorinated boronic acid ions (BF4-), 6-fluorinated phosphate ions (PF〆), perchloric acid ions (cl0〆), and 6 arsenic fluoride (AsF6-). At least one of a group consisting of 6 cesium fluoride (S b F6 ·), perfluoromethanesulfonyl (〇?3802-), and perfluorinated methanesulfonate 200836385 (CF3S〇r). Further, as the cation, a group consisting of a symmetrical four-stage ammonium ion, an ethylmethylimidazolium salt, a spiro-(1, fluorene) bispyridinium salt, or the like, and a lithium ion may be selected. . Among them, those containing lithium ions are preferred. Further, as a nonaqueous solvent, it may be derived from tetrahydrofuran (THF), methyltetrahydrofuran (MeTHF), formaldehyde, ethyl acetate, diethyl carbonate, dimethyl ether (DME), propylene carbonate (PC), r-butyl Carbene such as lactone (GBL), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethylene carbonate (EC), ethyl methyl carbonate (EMC), acetonitrile (AN), ring At least one selected from the group consisting of butyl sulfonium (SL) or a non-aqueous solvent containing fluorine as one of the molecules. The power storage device of the present invention contains the positive electrode, the negative electrode, the electrolytic solution, and a separator, and specific examples thereof include an electrochemical capacitor, a hybrid capacitor, a redox capacitor, an electric double layer capacitor, and a lithium battery. In the positive electrode and the negative electrode, a conductive material such as carbon black, acetylene black or ketjen black, and a binder such as a fluororesin or a water-soluble rubber resin are added to the positive electrode material and the negative electrode material, and are appropriately formed or coated. The separator may be a porous polyethylene film polypropylene film or the like. [Examples] Hereinafter, the examples of the present invention are disclosed, but the present invention is not limited thereto. -10-200836385 (Example 1) (Production of positive electrode) d(G()2) obtained by X-ray diffraction is 0.33 7 1 nm graphite (1 ), powder mixed with acetylene black and polytetrafluoroethylene resin (trade name · TAB, The Bulgarian Central Laboratory of Electrochemical Power Source), mixed at a weight ratio of 3:1, with agate The crucible was kneaded and formed into a circular shape having a diameter of 1 mm to obtain a particulate matter. The weight of the particles is 1 〇mg. The pellet was superposed on a screen made of aluminum as a current collector cut into a diameter of 10 mm, and pressed at 9 MPa to obtain a positive electrode (1). (Production of Negative Electrode) Anatase-type titanium dioxide, acetylene black, and tetrafluoroethylene resin having a specific surface area of 314 m2/g were mixed at a weight ratio of 5:4:1, and kneaded by agate, and formed into a diameter of 1 mm. The round shape gives the particles. The weight of the granules was 15 mg. The pellet was cut into a copper bouge of 10 m Hi as a current collector to obtain a negative electrode (1). (Manufacturing of Power Storage Device) The positive electrode (1) and the negative electrode (1) were vacuum dried at 200 ° C for 4 hours, and then assembled into a sealable coin type in a globe box having a dew point of -70 ° C or lower. In the test unit (cell). The test unit is made of stainless steel (SUS316) with an outer diameter of 20 mm and a height of 3 · 2 mm. The positive electrode (1) is such that the current collector is placed below the evaluation unit. -11 -

In the cans of 200836385, a film as a separator was placed thereon, and a mixture of ethylene carbonate and ethyl methyl carbonate obtained as a nonaqueous electrolyte at a concentration of 1 mol/L of LiPF6 was dropped therefrom. The viscous product ratio is 3:7 mixed). The current collector is placed on the upper negative electrode (i) with 0.5 mm thick spacers and springs (all manufactured) placed on it, and the upper part of the cans with the acrylic gasket is tight. The electricity storage device of the present invention was obtained by the above-mentioned method (Examples 2 to 6). In addition to changing the titanium oxide having a specific surface area of 314 m 2 /g in Example 1 to various titanium oxides shown in Table 1, The power storage device of the present invention (samples B to F) was obtained in the same manner as in the above (Example 7). Commercially available rutile-type high-purity titanium dioxide (PT-301: manufactured) 20.0 g and sodium carbonate 8.85 g. After mixing, the mixture was heated and fired in an electric furnace at a temperature of 800 ° C for 20 hours, and then heated and fired again under the same prayer to obtain a layered composition of Na 2 Ti 307, which was added to the layered sodium titanate obtained by adding 1 mol. The concentration of hydrochloric acid water was dissolved in a concentration of 10 g/L, and the reaction was allowed to proceed for 4 days. The reaction product was almost free of sodium, so that sodium was almost replaced by hydrogen, and it was confirmed to be a layered titanium oxide compound of H2Ti307. Further, in the reaction, the hydrazine was replaced with an aqueous hydrochloric acid solution. The obtained layered titanium oxide compound is dissolved in a thin layer of acryl (the body and the thickness of SUS316 are used thereon, (the sample is in the form of the second embodiment of the original gas in the gas production of sodium). Filtration, washing-12-200836385 Clean, solid-liquid separation, drying in air at 60 °C for 12 hours, heating in an electric furnace at 28 °C for 20 hours in the air to obtain titanium oxide (sample g). Further, using a differential thermal balance scale, the sample g is measured at a temperature of 300 to 600 ° C to obtain a heating loss of 1.0% by weight. This heating reduction is presumed to be from titanium oxide. The crystal water to be contained is considered to be a titanium oxide having a composition of Η 2 T i 2 2 Ο 4 5 , and the result of measuring the X-ray diffraction pattern of the sample g by the Cu-K α line as a radiation source is displayed. A pattern similar to the bronze type titanium dioxide shown in JCPDS card 3 5 -08 8 etc. However, the bronze type can observe (〇〇1) face and (200) at a diffraction angle (20) of 15 °. The two peaks of the surface, and the sample h, the interval between the two peaks is 〇 or very close. The X-ray diffraction pattern of the sample g shows In the same manner as in Example 1, except that the titanium oxide was changed to the sample g in the first embodiment, the power storage device (sample G) of the present invention (Example 8) was used. Lithium carbonate, and rutile-type titanium dioxide obtained by neutralizing and hydrolyzing titanium tetrachloride as titanium oxide, and mixing the ratio of K/Li/Ti to 3/1 / 6 · 5 The ground material was thoroughly ground. The ground material was transferred to a white gold crucible, and fired in an air oven at 800 ° C for 5 hours to obtain a layered lithium potassium titanate having a composition of Ko.sUmTiKuCU. 1 g of the layered lithium potassium titanate obtained was reacted for 1 day with stirring at room temperature with 1 liter of hydrochloric acid 1 〇〇 cm 3 '. As a result of analyzing the reaction product, almost no lithium or potassium was obtained. Therefore, lithium and potassium were almost replaced by hydrogen-13-200836385, and it was confirmed to be a layered titanium oxide compound. Then, it was filtered, washed with water, dried, and heated at 400 ° C for 20 hours in the air to obtain titanium oxide. (Sample h). The result of measuring the heating loss of the sample h of 3 00~6 00 °C is 0.1 2% by weight, as in the case of Example 8, it is estimated that the sample is a composition of H2Ti 18 903 79, and it is considered to be almost titanium dioxide (Ti02). Further, the sample h is measured by a Cu-K α line as a radiation source. As a result of the X-ray diffraction pattern, a pattern similar to the bronze type titanium dioxide shown by the JCPDS card 35-φ 088 or the like is shown. However, the bronze type is observed at a diffraction angle (20) of 44° (003). The surface has two peaks of the (-601) plane, and in the sample h, the interval between the two peaks is 0 or very close. The X-ray diffraction pattern of sample h is shown in Fig. 2. The electricity storage device (sample Η) of the present invention was obtained in the same manner as in Example 1 except that the titanium oxide was changed to titanium oxide in Example 1. (Example 9) • A layered titanium oxide compound having a composition of Hi.cwTh.uCU obtained in Example 8 in an amount equivalent to 0.4 g of Ti〇2 was added and dissolved in relation to the layered titanium oxide compound. The amount of H + in the solution was 10 0 cm 3 of an aqueous solution of 1 part by weight and equivalent of tetrabutylammonium hydroxide, and the vibrator was shaken to the extent of 150 reciprocations/min for 1 day, thereby peeling off the layered titanic acid. Anatase flaky titanium dioxide. As a result of the scanning probe microscopy, the enthalpy and length were about 0 · 2 to 1.0 // m, and the maximum thickness was about 1.5 nm. A power storage device (Sample I) of the present invention was obtained in the same manner as in Example 1 except that the flaky titanium oxide was used as the titanium oxide. -14-200836385 (Example 1 〇) Anatase-type titanium dioxide having a specific surface area of 314 m 2 /g obtained in Example 1 was dispersed in pure water by a juice machine to be liquefied, and added with respect to the above aqueous titanium hydroxide. After a 5% by weight of polyvinyl alcohol (Houpar PVA-204C: manufactured by Kuraray) was added in an amount of TiO2, pure water was added thereto, and the concentration was adjusted to a concentration of 10% by weight of Ti02. The above-mentioned slurry was spray-dried by a four-fluid nozzle type spray dryer (MDL-050B type: Fujisawa Electric Mechanism) at an inlet temperature of 200 ° C, an outlet temperature of 80 ° C, and an air discharge amount of 80 L/min. Secondary particles. The obtained secondary particles are heated and calcined in air at a temperature of 500 ° C for 3 hours, and then the heated calcined product is repulped with pure water, filtered, washed, solid-liquid separated, classified, and dried. Secondary particles of anatase type titanium dioxide are obtained. The average primary particle diameter (50% diameter of the volume basis obtained by electron microscopy) is 7 nm, and the average secondary particle diameter (average secondary particle diameter of the 50% diameter of the volume basis obtained by the laser scattering method) is 7 nm. The distance is 9 · 2 nm, and the amount of void is 〇 5 5 2 c m3 / g. The electricity storage device (sample J) of the present invention was obtained in the same manner as in Example 1 except that the secondary particles were used as the cerium oxide. (Example 1 1) Except that an anatase type titanium oxide having a specific surface area of 3 14 m 2 /g was used instead of the layered titanium oxide compound having the composition of H2Ti307 obtained in Example 7 as a negative electrode active material, In the same manner as in Example 1, the power storage device (sample κ) of the invention of 200836385 was obtained. (Example 1 2) The layered sodium titanate having the composition of Na2Ti3〇7 obtained in Example 7 was used as a composite oxide containing titanium and an alkali metal in place of anatase type titanium dioxide having a specific surface area of 3 14 m 2 /g. The power storage device (sample L) of the present invention was obtained in the same manner as in the example except that the weight of the particulate matter was 6 〇 mg. (Examples 13 to 20) In place of the graphite (3) in which d(〇〇2) of 0.3368 (d) or d(G()2) of 0.33 63 obtained by X-ray diffraction was used instead of the example In the same manner as in Example 1, except for the graphite (1) used in the first step, the power storage device (sample Μ to T) of the present invention was obtained. (Comparative Example 1) A power storage device (sample U) to be compared was obtained in the same manner as in Example 1 except that the commercially available activated carbon was used instead of the dioxins as the negative electrode material. (Comparative Example 2) A power storage device to be compared was obtained in the same manner as in Example 除了 except that the commercially available activated carbon used in Comparative Example 1 was used instead of graphite (1) as the positive electrode material in Example 1. Sample V). 200836385

Evaluation 1: Measurement of specific surface area The specific surface area of the positive electrode material and the negative electrode material used in Examples 1 to 20 and Comparative Examples 1 and 2 was measured by a BET method using a specific surface area measuring apparatus (Monosorb: manufactured by Yuas a-Ionics). The results are shown in Table 1. -17- 200836385 『Table i】 Example sample Cathode material Anode material Material specific surface area (m2/g) Material specific surface area (m2/g) Example 1 A Graphite (1) 20 Anatase TiO2 (ST-01: Ishihara Industrial Co., Ltd. 314 Example 2 B ” Anatase type Ti〇2 (ST-21: manufactured by Ishihara Sangyo Co., Ltd.) 62 Example 3 C ′′ Anatase type Ti02 (ST-41: manufactured by Ishihara Sangyo Co., Ltd.) 10 Example 4 D ” rutile type Ti02 (MPT-851: manufactured by Ishihara Sangyo Co., Ltd.) 190 Example 5 E ” Anatase TiO2 containing rutile type 58% (PT-401M: manufactured by Ishihara Sangyo Co., Ltd.) 20 Example 6 F Anatase-type flaky TiO2 (TF-4: manufactured by Ishihara Sangyo) 12 Example 7 G ′′ Similar to bronze type H2T122O45 5 Example 8 ” ” Similar to bronze type Ti〇2 12 Example 9 I ” ” sharp Titanium-type flake-like Ti〇2 127 Example 10 J ” Anatase type (secondary particle) TiO2 (ST-01 ··Ishihara Industry Co., Ltd.) 95 Example 11 K ” Layered titanic acid H2Ti3〇7 5 Example 12 L " " Layered sodium titanate Ν 2 Τΐ 3 〇 7 3 Example 13 石墨 Graphite (2) 3 Anatase TiO 2 (ST-01: manufactured by Ishihara Sangyo Co., Ltd.) 3 14 Example 14 N ′′ Anatase type Ti02 (ST-21: manufactured by Ishihara Sangyo Co., Ltd.) 62 Example 15 0 ” Anatase type Ti02 (ST_41: manufactured by Ishihara Sangyo Co., Ltd.) 10 Example 16 P ” Anatase Type (secondary particle) TiO2 (ST-01: manufactured by Ishihara Sangyo Co., Ltd.) 95 Example 17 Q Graphite (3) 4 Anatase TiO 2 (ST-01: manufactured by Ishihara Sangyo Co., Ltd.) 314 Example 18 R ” Anatase type Ti02 (ST-21: manufactured by Ishihara Sangyo Co., Ltd.) 62 Example 19 S ′′ Zhongjing type Ti02 (ST-41: manufactured by Ishihara Sangyo Co., Ltd.) 10 Example 20 T ” Anatase type (secondary particle) TiO2 (ST- 01: Ishihara Industrial System) 95 Comparative Example 1 u Graphite (1) 20 Activated Carbon 1800 Comparative Example 2 V Activated Carbon 1800 Anatase TiO2 (ST-01: manufactured by Ishihara Sangyo) 314 -18- 200836385 Evaluation 2: Evaluation of Capacitance The electric capacities of the electricity storage devices (samples A to V) obtained in Examples 1 to 20 and Comparative Examples 1 and 2 were evaluated. For each sample, the setting of the charger was set to a constant current of 0.3 mA. After charging to 3.5V as the charging voltage for 2 hours, the discharge capacity at the time of discharge to ^. 3 ^A, 1 V was taken as the capacity of the sample (mAh/g (positive electrode) The living substance)) is shown in Table 2. Further, discharge curves of Samples A to L, N, and R are shown in Figs. 3 to 18. The φ discharge curve, the voltage axis slice, the capacitance slice and the area enclosed by the origin are equivalent to the energy of the power storage device, and the larger the area, the greater the energy.

-19- 200836385 Table 2]

EXAMPLES Sample Capacity (mAh/g) Example 1 A 76.5 Example 2 B 72.8 Example 3 C 70.5 Example 4 D 46.2 Example 5 E 43.8 Example 6 F 65.7 Example 7 G 53.7 Example 8 57.9 Example 9 I 53.5 Example 10 J 76.4 Example 11 κ 64.6 Example 12 L 42.6 Example 13 Μ 65.9 Example 14 N 62.6 Example 15 0 54.5 Example 16 P 62.9 Example Π 0 67.4 Example 18 R 64.7 Example 19 S 56.2 Example 20 T 64.4 Comparative Example 1 U 46.1 Comparative Example 2 V 26.4 Evaluation 3 : Cycle characteristics The power storage devices (samples A to L) obtained in Examples 1 to 2 were subjected to Repetitive feature evaluation. For each sample, the charge and discharge current was set to 0.3 mA, and after charging at a constant current of 3.3 V, the discharge was performed to 1.0 V in the same manner, and the charge and discharge cycle of 30 cycles was repeated. The charge/discharge capacity of the second cycle and the 30th cycle was measured, and it was used as the capacity of -20-200836385, and the capacity of (the capacity of the third cycle / the capacity of the second cycle) X 1 00 was used as the reusability characteristic. . The results are shown in Table 3. Further, the change in the capacity retention rate of Example 1 is shown in Fig. 19.

[Table 3] Example Sample Capacity (mAh/g) Reuse Characteristics 2nd Cycle 30th Cycle Example 1 A 46.9 45.0 95.9 Example 2 B 43.7 38.3 87.6 Example 3 C 43.3 43.5 100.5 Example 4 * D 39.7 40.5 102.0 Example 5 E 43.6 40.5 92.9 Example 6 F 43.6 42.0 96.3 Example 7 G 32.5 18.2 56.0 Example 8 Η 38.8 33.0 85.1 Example 9 I 40.9 45.0 110.0 Example 10 J 45.6 43.6 95.6 Example 11 K 54.0 54.3 100.6 Example 12 L 28.5 27.9 97.6 Evaluation 4: Evaluation of power characteristics The power storage devices obtained in Examples 1, 2, 4, 7, 9, and 10 (samples A, B, D, G, I) , J) Evaluation of power characteristics. For each sample, charge and discharge were performed in a range of a voltage range of 1 to 33 to 3 V, a charging current of 40 mA/g, and a discharge current of 40 to 1600 mA/g, and the respective discharge capacities were measured. The capacity retention rate is calculated by measuring the discharge capacity of 40 mA/g 値 as X 1 and measuring 値 in the range of 80 to 1 600 m A / g as Xn by (Xn) /X! ) The formula of xlOO is found. The results are shown in Table 4. -21 - 200836385. It can be judged that even if the amount of current is increased, excellent power characteristics can be obtained as long as the capacity retention rate is high. [Table 4]

EXAMPLES Sample Capacity Maintenance Rate (%) 80 mA/g 160 mA/g 320 mA/g 800 mA/g 1600 mA/g Example 1 A 99.1 98.5 97.3 93.1 86.0 Example 2 B 97.1 94.2 92.4 91.7 61.6 Example 4 D 98.1 95.1 92.1 85.8 75.2 Example 7 G 95.2 90.0 83.2 68.9 52.8 Example 9 I 96.7 92.1 86.6 81.4 62.7 Example 10 J 101.7 102.7 101.0 95.8 89.3 (Example 2 1 ) Production of positive electrode The same as used in Example 1 Graphite (1) 3 g, acetylene black and tetrafluoroethylene mixed powder (TAB) 1 g, mixed with agate enamel, pressed on the substrate, punched into a circle with a diameter of 12 mm to obtain a living substance. A positive electrode (2) having a quantity of j 〇 mg and a thickness of about 0.1 mm. Preparation of the negative electrode The sharp-mining type titanium dioxide 3 g and TAB 1 g ' used in the examples were 1983 m 2 /g, and were mixed with agate, and pressed on the substrate to be punched into a circle of diameter mm. In the shape, a negative electrode (2) having a temporary dose of 10 mg and a thickness of about 0.1 mm was obtained. Manufacture of Power Storage Device -22- 200836385 The same procedure as in Example 1 was carried out except that the positive electrode (1) and the negative electrode (1) in Example 1 were changed to the positive electrode (2) and the negative electrode (2), respectively. The power storage device (sample A,) of the invention. (Examples 22 to 29) The same procedure as in Example 21 was carried out, except that various titanium oxides shown in Table 5 were used instead of the anatase type titanium oxide having a specific surface area of 3 14 m 2 /g in Example 21. Power storage device of the present invention (sample B, evaluation 5) Measurement of specific surface area The specific surface area of the titanium oxide used in Examples 2 to 29 was measured in the same manner as in Evaluation 1. The results are shown in Table 5.

-23- 200836385 [Table 5] Example Sample Positive electrode material Anode material specific surface area (m2/g) Example 21 A5 Stone·1) Anatase type TiO2 (ST-01: manufactured by Ishihara Sangyo Co., Ltd.) 314 Example 22 B " Anatase type Ti02 (ST-21: manufactured by Ishihara Sangyo Co., Ltd.) 62 Example 23 C, " Anatase type Ti02 (ST-41: manufactured by Ishihara Sangyo Co., Ltd.) 10 Example 24 D, " Anatase type ΉΟ 2 ( ΡΤ-501Α: Ishihara Industrial Co., Ltd. 17 Example 25 E, "Rutile-type Ti02 (CR-EL: manufactured by Ishihara Sangyo) 7 Example 26 F," Rutile type Ή02 (ΜΡΤ·851: Ishihara Sangyo Co., Ltd.) 190 Implementation Example 27 G, rutile type Ti02 (TT0-55N: manufactured by Ishihara Sangyo Co., Ltd.) 42 Example 28 H, "Rutile type Ti02 (TT0-55A: manufactured by Ishihara Sangyo Co., Ltd.) 40 Example 29 ” " Contains rutile type 58% Anatase TiO2 (PT-401M, manufactured by Ishihara Sangyo Co., Ltd.) 20 Evaluation 6: Evaluation of capacitance The capacitances of the electricity storage devices (samples A' to I') obtained in Examples 21 to 29 were evaluated. After applying a charging current to a power storage device of sample A' to 以 at a constant current of 1 mA, the voltage is switched to a constant voltage at a point of 3.5 V for a total of 2 hours of charging, and then discharged to 1 mA and 0 V to discharge. The capacity is shown in Table 6 as the capacitance of the sample (mAh/g (positive active material)). -24 - 200836385 [Table 6] Example Sample Capacity (mAh/g) Example 21 A, 62 Example 22 B, 72 Example 23 C, 68 Example 24 D, 71 Example 25 E, 24 Implementation Example 26 F 50 Example 27 G5 35 Example 28 H, 33 Example 29 Γ 44 The electric storage device of the present invention has a large capacity. Further, as seen in the comparison of Examples 4, 5, and 12 with Comparative Example 1, in the present invention, even if the capacitance is not too large, the electric energy is large because the discharge voltage is high. Therefore, it can be known that high energy density can be achieved. Moreover, the reusability characteristics and power characteristics are also excellent. (Industrial Applicability) The power storage device of the present invention is useful for a power source for a mobile body such as an electric vehicle or a power system for powering a case. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an X-ray diffraction pattern of a titanium oxide (sample g) obtained in Example 7. Figure 2 is an embodiment of a diffraction pattern. Titanium oxide obtained in the sample (sample h) (X-ray-25-200836385 FIG. 3 is a discharge graph of the electricity storage device (sample A) obtained in Example 1. FIG. 4 is a power storage device obtained in Example 2. Fig. 5 is a discharge graph of the electricity storage device (sample C) obtained in Example 3. Fig. 6 is a discharge curve of the electricity storage device (sample D) obtained in Example 4. Fig. 7 is a discharge graph of the electricity storage device (sample E) obtained in Example 5. Fig. 8 is a discharge graph of the electricity storage device (sample F) obtained in Example 6. Fig. 9 is a seventh embodiment. The discharge curve of the electricity storage device (sample G) obtained in Fig. 1 is a discharge curve of the electricity storage device (sample Η) obtained in Example 8. Fig. 1 is the electricity storage device obtained in Example 9 ( Fig. 12 is a discharge graph of the electricity storage device (sample J) obtained in Example 10. Fig. 13 is a discharge curve of the electricity storage device (sample Κ) obtained in Example 11. Fig. 14 is a discharge graph of the electricity storage device (sample L) obtained in Example 12. -26- 200836385 Fig. 1 5 is a discharge graph of the electricity storage device (sample N) obtained in Example 14. Fig. 16 is a discharge graph of the electricity storage device (sample R) obtained in Example 18. Fig. 17 is a comparative example Fig. 18 is a discharge graph of the electricity storage device (sample V) obtained in Comparative Example 2. Fig. 19 is a power storage device obtained in Example 1. A graph of the cycle characteristics of sample A).

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Claims (1)

200836385 X. Patent Application No. 1. A power storage device characterized by comprising: a cathode material containing graphite, containing a material selected from the group consisting of Ti, Zr, V, Cr, Mo, Mn, Fe, Co, Ni, Cu, Zn, Sn And a negative electrode material of an oxide of at least one of the metal elements of Sb, Bi, W, and Ta, and an electrolyte. 2. The power storage device of claim 1, wherein the oxide of the metal element is a metal oxide containing at least ruthenium as a metal element. 3. The power storage device of claim 2, wherein the metal oxide is titanium oxide. 4. The power storage device of claim 3, wherein the titanium oxide has a crystalline form of anatase and/or rutile. 5. The power storage device of claim 3, wherein the titanium oxide is a layered titanium oxide compound heated. 6. The power storage device of claim 3, wherein the cerium oxide is a secondary particle formed by a primary particle collection. 7. A livestock electric device of claim 3, wherein the specific surface area of the niobium oxide is in the range of 0.1 to 500 m 2 /g. 8. The power storage device of claim 3, wherein the particle shape of the zirconia oxide is flake-shaped. 9. A livestock electrical device as claimed in claim 2, wherein the metal oxide is a composite oxide of titanium and an alkali metal or alkaline earth metal element. 1 〇 A petal apparatus according to item 1 of the patent application, wherein the specific surface area of graphite is in the range of 0.5 to 300 m 2 /g. 1 1 The power storage device of claim 1, wherein an electrolyte containing a nonaqueous solvent and a lithium salt is used. -28-